Excisional biopsy devices and methods

ABSTRACT

An excisional biopsy device includes a tubular member having a window near a distal tip thereof; a cutting tool, a distal end of the cutting tool being attached near the distal tip of the tubular member, at least a distal portion of the cutting tool being configured to selectively bow out of the window and to retract within the window; and a tissue collection device externally attached at least to the tubular member, the tissue collection device collecting tissue excised by the cutting tool as the biopsy device is rotated and the cutting tool is bowed. An excisional biopsy method for soft tissue includes the steps of inserting a generally tubular member into the tissue, the tubular member including a cutting tool adapted to selectively bow away from the tubular member and an external tissue collection device near a distal tip of the tubular member; rotating the tubular member; selectively varying a degree of bowing of the cutting tool; collecting tissue severed by the cutting tool in the tissue collection device; and retracting the tubular member from the soft tissue. The tubular member may include an imaging transducer and the method may include the step of displaying information received from the transducer on a display device and the step of varying the degree of bowing of the cutting tool based upon the displayed information from the imaging transducer. Alternatively, the imaging transducer may be disposed within a removable transducer core adapted to fit within the tubular member.

This application is a divisional of U.S. application Ser. No. 09/146,743filed Sep. 3, 1998 now U.S. Pat. No. 6,022.362.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to the field of soft tissue excisionalbiopsy devices and methods. In particular, the present invention relatesto the field of devices and methods for excising suspicious lesions fromsoft tissue, such as breast tissue.

2. Description of the Related Art

Breast cancer is a major threat and concern to women. Early detectionand treatment of suspicious or cancerous lesions in the breast has beenshown to improve long term survival of the patient. The trend is,therefore, to encourage women not only to perform monthly self-breastexamination and obtain a yearly breast examination by a qualifiedphysician, but also to undergo annual screening mammography commencingat age 40. Mammography is the only screening modality available todaythat can detect small, nonpalpable lesions. These nonpalpable lesionsmay appear as opaque densities relative to normal breast parenchyma andfat or as clusters of microcalcifications.

The conventional method for diagnosing, localizing and excisingnonpalpable lesions detected by mammography generally involves atime-consuming, multi-step process. First, the patient goes to theradiology department where the radiologist finds and localizes thelesion either using mammography or ultrasound guidance. Once localized,a radio-opaque wire is inserted into the breast. The distal end of thewire may include a small hook or loop. Ideally, this is placed adjacentto the suspicious area to be biopsied. The patient is then transportedto the operating room. Under general or local anesthesia, the surgeonperforms a procedure called a needle-localized breast biopsy. In theneedle-localized breast biopsy, the surgeon, guided by the wirepreviously placed in the patient's breast, excises a mass of tissuearound the distal end of the wire. The specimen is sent to the radiologydepartment where a specimen radiograph is taken to confirm that thesuspicious lesion is contained within the excised specimen. Meanwhile,the surgeon, patient, anesthesiologist and operating room staff, wait inthe operating room for confirmation of that fact from the radiologistbefore the operation is completed. The suspicious lesion should ideallybe excised in toto with a small margin or rim of normal breast tissue onall sides. Obtaining good margins of normal tissue is extremelydependent upon the skill and experience of the surgeon, and often anexcessively large amount of normal breast tissue is removed to ensurethat the lesion is located within the specimen. This increases the riskof post-operative complications, including bleeding and permanent breastdeformity. As 80% of breast biopsies today are benign, many womenunnecessarily suffer from permanent scarring and deformity from suchbenign breast biopsies.

More recently, less invasive techniques have been developed to sample orbiopsy the suspicious lesions to obtain a histological diagnosis. Thesimplest of the newer techniques is to attempt visualization of thelesion by external ultrasound. If seen by external ultrasound, thelesion can be biopsied while being continuously visualized. Thistechnique allows the physician to see the biopsy needle as it actuallyenters the lesion, thus ensuring that the correct area is sampled.Current sampling systems for use with external ultrasound guidanceinclude a fine needle aspirate, core needle biopsy or vacuum-assistedbiopsy devices.

Another conventional technique localizes the suspicious lesion usingstereotactic digital mammography. The patient is placed prone on aspecial table that includes a hole to allow the designated breast todangle therethrough. The breast is compressed between two mammographyplates, which stabilizes the breast to be biopsied and allows thedigital mammograms to be taken. At least two images are taken 30 degreesapart to obtain stereotactic views. The x, y and z coordinates targetingthe lesion are calculated by a computer. The physician then aligns aspecial mechanical stage mounted under the table that places the biopsydevice into the breast to obtain the sample or samples. There arebelieved to be three methods available to biopsy lesions using astereotactic table: (1) fine needle aspiration, (2) core needle biopsyand (3) vacuum-assisted core needle biopsy.

Fine needle aspiration uses a small gauge needle, usually 20 to 25gauge, to aspirate a small sample of cells from the lesion or suspiciousarea. The sample is smeared onto slides that are stained and examined bya cytopathologist. In this technique, individual cells in the smears areexamined, and tissue architecture or histology is generally notpreserved. Fine needle aspiration is also very dependent upon the skilland experience of the operator and can result in a high non-diagnosticrate (up to about 83%), due to inadequate sample collection orpreparation.

Core needle biopsy uses a larger size needle, usually 14 gauge to samplethe lesion. Tissue architecture and histology are preserved with thismethod. A side-cutting device, consisting of an inner trough with anouter cutting cannula is attached to a spring-loaded device for a rapidsemi-automated firing action. After the lesion is localized, localanaesthetic is instilled and a small incision is made in the skin with ascalpel. The device enters the breast and the needle tip is guided intothe breast up to the targeted lesion. The device is fired. First, theinner cannula containing the trough rapidly penetrates the lesion.Immediately following this, the outer cutting cannula rapidly advancesover the inner cannula cutting a sample of tissue off in the trough. Thewhole device is then removed and the sample retrieved. Multiplepenetrations of the core needle through the breast and into the lesionare required to obtain an adequate sampling of the lesion. Over 10samples have been recommended by some.

The vacuum-assisted breast biopsy system is a larger semi-automatedside-cutting device. It is usually 11 gauge in diameter and is moresophisticated than the core needle biopsy device. Multiple large samplescan be obtained from the lesion without having to reinsert the needleeach time. A vacuum is added to suck the tissue into the trough. Therapid firing action of the spring-loaded core needle device is replacedwith an oscillating outer cannula that cuts the breast tissue off in thetrough. The physician controls the speed at which the outer cannulaadvances over the trough and can rotate the alignment of the trough in aclockwise fashion to obtain multiple samples.

If a fine needle aspirate, needle core biopsy or vacuum-assisted biopsyshows malignancy or a specific benign diagnosis of atypical hyperplasia,then the patient needs to undergo another procedure, the traditionalneedle-localized breast biopsy, to fully excise the area with anadequate margin of normal breast tissue. Sometimes the vacuum-assisteddevice removes the whole targeted lesion. If this occurs, a smalltitanium clip should be placed in the biopsy field. This clip marks thearea if a needle-localized breast biopsy is subsequently required forthe previously mentioned reasons.

Another method of biopsying the suspicious lesion utilizes a largeend-cutting core device measuring 0.5 cm to 2.0 cm in diameter. Thisalso uses the stereotactic table for stabilization and localization.After the lesion coordinates are calculated and local anesthesiainstilled, an incision large enough is permit entry of the bore is madeat the entry site with a scalpel. The breast tissue is cored down to andpast the lesion. Once the specimen is retrieved, the patient is turnedonto her back and the surgeon cauterizes bleeding vessels under directvision. The incision, measuring 0.5 to larger than 2.0 cm is suturedclosed.

The stereotactic table requires awkward positioning of the patient andmay be extremely uncomfortable. The woman must lie prone during theentire procedure, which may be impossible for some patients. Inaddition, the lesion to be biopsied must be in the center working areaof the mammography plates. This may be extremely difficult anduncomfortable for the patient if the lesion is very posterior near thechest wall or high towards the axilla.

The woman is subjected to increased radiation exposure as multipleradiographs are required throughout the course of the procedure to: (1)confirm that the lesion is within the working area of the mammographyplates, (2) obtain the stereotactic coordinates (at least two views),(3) verify the positioning of the biopsy needle prior to obtainingtissue, and (4) verify that the lesion was indeed sampled. If anydifficulty is encountered during the procedure, additional radiographicexposures are required to verify correction of the problem.

Using the core needle biopsy or vacuum-assisted device, bleeding iscontrolled only by manual pressure. Bleeding is generally not an issuewith fine needle aspiration, but is a legitimate complication of theformer two methods. Ecchymoses, breast edema and hematomas can occur.This causes increased post-procedural pain and delays healing. Rarely,the patient may require an emergency operation to control and evacuate atense hematoma.

Another major concern is the possibility of tumor dissemination. Thecore needle biopsy and vacuum-assisted devices both cut into the tumorand carve out multiple samples for examination. While cutting into thetumor, cancerous cells may be dislodged. Cutting across blood vessels atthe same time may allow the freed cancerous cells access to the bloodstream, thus possibly seeding the tumor beyond its original locus. Thelong-term consequences of tumor seeding with the risk of bloodbornemetastases are unknown at this time, as the techniques are relativelynew. However, documented instances of cancerous cells seeding locallyinto needle tracks exist. There are numerous reports of metastasesgrowing in needle tracks from previous biopsies of a cancerous mass.Most of these are from lung or liver cancers. However, at least one caseof mucinous carcinoma of the breast growing in a needle track has beenreported. The long-term consequences of neoplasm seeding into needletracks are currently unknown, again because the techniques arerelatively new. Some recommend excision of the entire needle track,including the skin entry site, during the definitive surgical procedurefor a diagnosed cancer, whether it be a lumpectomy or a mastectomy.Others assume that with a lumpectomy, the post-operative radiationtherapy will destroy any displaced cancer cells in the needle track.With the trend towards treating very small cancers only by excision andwithout a post-excision course of radiation therapy, the risk of cancercells metastasizing and growing in needle tracks is very real.

The large core cutting device (0.5 to 2.0 cm) generally eliminates therisk of needle track seeding as it is designed to excise the lesionintact. A stereotactic table is required with the same inherentawkwardness for the patient, as discussed above. Bleeding is controlled,albeit manually, requiring that the patient wait until the end of theprocedure to be turned over. Compression is used to stabilize the breastand localize the lesions. The breast, however, may be torqued anddistorted between the compression plates such that when the plates areremoved after the biopsy, the large core track left behind may not bestraight, but actually tortuous. This can result in permanent breastdeformity.

The location of the insertion site into the breast is dictated by thepositioning of the breast in the machine and not by the physician. Theentry site is usually away from the nipple-areolar complex and isusually located on the more exposed areas of the breast. For the fineneedle aspirate, core biopsy and vacuum-assisted devices, the incisionis usually very small and the scar almost unappreciable. However, in thecase of the large core biopsy device (0.5 to 2.0 cm), a large incisionis needed. Such a large incision often results in a non-aestheticallyplaced scar.

The newer conventional minimally invasive breast biopsy devices haveimproved in some ways the ability to diagnose mammographically detectednonpalpable lesions. These devices give the patient a choice as to howshe wants the diagnosis to be made. Moreover, these devices aresubstantially less expensive than the older traditional needle-localizedbreast biopsy. They are not, however, the final solution. Due to theabove-discussed problems and risks associated with compression,needle-track seeding, blood borne metastases, bleeding, radiationexposure and awkwardness of the stereotactic table, more refined devicesand methods are needed to resolve these issues. Also, the conventionalbiopsy devices do not consider margins in their excisions and if canceris diagnosed, the patient must undergo a needle-localized breastlumpectomy to ensure that adequate margins are removed around thecancer. Devices and methods, therefore, must address the problem ofobtaining adequate margins so that a second procedure is not required.Margins, moreover, cannot be assessed while the breast is beingcompressed.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide devicesand methods to efficiently and safely excise suspicious lesions from thebreast. It is also an object of the present invention to provide devicesand methods that remove the entire lesion intact with the minimum amountof normal tissue surrounding the lesion needed to provide adequatemargins. It is a further object of the present invention to providedevices and methods that provide hemostasis in the breast to minimizecomplications of ecchymosis, hematoma formation, and breast edema. It isanother object of the present invention to provide methods and devicesto provide intra-tissue ultrasonic guidance to provide real time, insitu monitoring of the procedure. A still further object is to providedevices and methods that allow the physician to minimize the size of theincision though which the procedure is performed and to leave anaesthetically acceptable scar on the breast.

In accordance with the above-described objects and those that will bementioned and will become apparent below, an embodiment of an excisionalbiopsy device according to the present invention comprises:

a tubular member having a window near a distal tip thereof;

a cutting tool, a distal end of the cutting tool being attached near thedistal tip of the tubular member, at least a distal portion of thecutting tool being configured to selectively bow out of the window andto retract within the window; and

a tissue collection device externally attached at least to the tubularmember, the tissue collection device being adapted to collect a tissuesample severed by the cutting tool as the biopsy device is rotated andthe cutting tool is bowed.

According to further embodiments, the distal portion of the cutting toolmay comprise a thin ribbon sharpened on a leading edge thereof. Theleading edge of the thin ribbon may be serrated. The tubular member maycomprise an internal guide allowing a proximal portion of the cuttingtool to slide therein when a proximal end of the cutting tool is pushedin a distal direction or pulled in a proximal direction. The cuttingtool may further comprise an interior lumen; and a plurality of throughholes in the distal portion thereof, the through holes being in fluidcommunication with the interior lumen. The tissue collection device maycomprise a bag within which the excised sample of tissue is collected.An opening of the bag may be at least co-extensive with the window inthe tubular member. The tissue collection device may be configured toopen and to close as the cutting tool is selectively bowed andretracted, respectively. The tissue collection device may comprise a bagattached to the tubular member and to a trailing edge of the distalportion of the cutting tool, the bag opening and closing as the cuttingtool is bowed and retracted, respectively. An ultrasound sensor may bemounted within the distal portion of the tubular member, the ultrasoundsensor being disposed within the tubular member so as to image tissueabout to be cut by the cutting tool as the biopsy device is rotated. Theultrasound sensor may be electrically connected to at one or more dataprocessing and display devices to allow either a real time or a nearreal time graphical representation of the tissue to be cut. The distalportion of the cutting tool may be electrically connected to an RF orother power source. The distal portion of the cutting tool may comprisea thin wire.

An invasive interventional device for soft biological tissue, accordingto a further embodiment of the present invention, comprises

a rotatable tubular member having a distal tip adapted to penetrate thetissue;

a work element disposed near the distal tip of the tubular member, thework element acting upon the tissue coming into contact therewith as thetubular member rotates;

an ultrasound transducer disposed near the distal tip of the tubularmember and away from the work element, so that the transducer sweeps aplane within the tissue ahead of the work element as the tubular memberrotates; and

means for controlling an operation of the work element based uponinformation gathered from the ultrasound transducer.

According to still further embodiments, the ultrasound transducer may betuned within a range from about 7.5 MHz to about 20 MHz. The ultrasoundtransducer may be disposed within the tubular member at an angle αrelative to the work element, the angle α being no smaller than thatnecessary to effectively control the operation of the work element inresponse to the information gathered from the transducer as the tubularmember rotates. The angle α is preferably less than about 180 degrees.The work element may comprise at least one device selected from thegroup consisting of: an abrasive device, a reciprocating cutting device,a bowing cutting device, an electrosurgical device, a laser device and avibrating device. The ultrasonic transducer may be connected to at leastone data processing and display device to allow an operator of thedevice to ascertain a structure of the tissue and to control theoperation of the work element before the tissue comes into contact withthe work element as the device rotates. The work element may comprise acutting tool, a distal end of the cutting tool being attached near thedistal tip of the tubular member, at least a distal portion of thecutting tool being configured to selectively bow out of a window in thetubular member and to retract within the window. The controlling meansmay include means for selectively bowing and retracting the cuttingtool.

According to yet another embodiment, an excisional biopsy method forsoft tissue, according to the present invention, comprises the steps of:

inserting a generally tubular member into the tissue, the tubular memberincluding a cutting tool adapted to selectively bow away from thetubular member and an external tissue collection device near a distaltip of the tubular member;

rotating the tubular member;

selectively varying a degree of bowing of the cutting tool;

collecting tissue severed by the cutting tool in the tissue collectiondevice; and

retracting the tubular member from the soft tissue.

The rotating step may be carried out by manually rotating the tubularmember. The tubular member may further include an imaging transducer andthe method may further include the steps of displaying informationreceived from the transducer on a display device; and varying the degreeof bowing of the cutting tool based upon the displayed information fromthe imaging transducer. The cutting tool may comprise an electrosurgicalblade and the method may further comprise the step of varying the power(for example, RF power) applied to the electrosurgical blade based uponinformation received from the transducer. A step of stabilizing the softtissue in an uncompressed state prior to the inserting step may also becarried out. A step of controlling the cutting tool to assume anon-extended state may be carried out prior to the inserting step andbefore the retraction step. The tissue collection device assumes aclosed configuration when the cutting tool assumes the non-extendedstate. The extension of the cutting tool may be controlled byselectively and manually pushing and retracting a proximal end of thecutting tool in the distal and proximal directions, respectively. Thecutting tool may comprise an interior lumen and a plurality of throughholes in fluid communication therewith, and the method may furthercomprise the step of delivering at least one fluid to the tissue via theplurality of through holes.

The present invention may also be viewed as an imaging and treatmentmethod for soft tissue, comprising the steps of:

inserting a tubular member into the soft tissue, the tubular memberincluding an ultrasonic transducer mounted near a distal end of thetubular member;

rotating the tubular member within the soft tissue;

displaying an output of the ultrasonic transducer on a display device;and

acting upon the soft tissue based upon the displayed output.

According to further preferred embodiments, the ultrasonic transducermay be tuned to within a frequency range of between about 7.5 MHz toabout 20 MHz. The acting step may include a step of severing aselectively variable volume of soft tissue from a main tissue mass. Astep of collecting the severed volume of tissue in a tissue collectiondevice mounted externally to the tubular member may also be carried out.

According to a further embodiment, an excisional biopsy device,according to the present invention, comprises:

a tubular member having a first and a second window near a distal tipthereof;

a cutting tool configured to selectively bow out of the first window andto retract within the first window; and

a removable transducer core, the transducer core including an activetransducer element configured to face out of the second window when theremovable transducer core is fitted within the tubular member.

The removable core may be adapted to snap fit within the tubular member.The active transducer element may, for example, include an ultrasoundtransducer. The removable transducer core may include a tapered distaltip configured to readily penetrate soft tissue. An external tissuecollection device may be attached to the cutting tool and/or to thetubular member. The tubular member may further comprise a recessedsection adjacent a trailing edge of the cutting tool, the recessedsection being adapted to receive the external tissue collection device.An expandable sheath may also be included, the expandable sheath beingadapted to receive the removable transducer core and the tubular member.

The present invention may also be viewed as a method of excising alesion from soft biological tissue using an excisional biopsy systemincluding a generally tubular member having a cutting tool, a removabletransducer core adapted to fit within the tubular member and anexpandable sheath, comprising the steps of:

fitting the transducer core through the expandable sheath,

inserting the transducer and sheath though an incision in the tissue;

imaging a target site within the tissue by energizing the transducercore,

removing the transducer core from sheath while leaving the sheath inplace within the tissue;

securing the core within the generally tubular member so the core facesoutwardly from the tubular member;

sliding the tubular member through the expandable sheath until thecutting tool is positioned adjacent the lesion;

cutting the lesion with the cutting tool; and

retracting at least the tubular member from the incision.

A step of stabilizing the breast in one of an uncompressed and aslightly expanded state prior to the inserting step may also be carriedout. The sheath may remain within the tissue after the retracting stepand the method may further comprise the step of re-inserting thetransducer core within the sheath and imaging the target site to insurethat the lesion has been excised. A step of collecting the cut lesionwithin an external tissue collection device secured to the tubularmember may also be carried out. Both the tubular member and the sheathmay be retracted from the incision.

The present invention may also be viewed as an excisional biopsy device,comprising:

a single use disposable tubular member having a window near a distal tipthereof, the tubular member including a cutting tool, a distal end ofthe cutting tool being attached near the distal tip of the tubularmember, at least a distal portion of the cutting tool being configuredto selectively bow out of the window and to retract within the window;and

a single use disposable tissue collection device externally attached atleast to the tubular member, the tissue collection device collectingtissue severed by the cutting tool as the biopsy device is rotated andthe cutting tool is bowed.

In yet another embodiment, the present invention is an excisional biopsydevice, comprising:

a single use disposable tubular member having a first and a secondwindow near a distal tip thereof, the tubular member including a cuttingtool configured to selectively bow out of the first window and toretract within the first window; and

a removable transducer core, the transducer core including an activetransducer element configured to face out of the second window when theremovable transducer core is fitted within the tubular member.

BRIEF DESCRIPTION OF THE DRAWINGS

For a further understanding of the objects and advantages of the presentinvention, reference should be made to the following detaileddescription, taken in conjunction with the accompanying figures, inwhich:

FIG. 1A shows an embodiment of the excisional device according to thepresent invention with the cutting tool in its flat, retractedconfiguration.

FIG. 1B shows the excisional device of FIG. 1A with its cutting tool inan extended, bowed configuration.

FIG. 1C shows another view of the excisional device of FIG. 1A.

FIG. 2A depicts the distal region of another embodiment of theexcisional device according to the present invention, showing theexcisional device together with the external tissue collection attachedthereto in the open configuration.

FIG. 2B shows the excisional device of FIG. 2A together with theexternal tissue collection attached thereto in the closed configuration.

FIG. 2C shows an embodiment of the proximal region of the excisionaldevice according to the present invention.

FIG. 3A depicts the operation of an embodiment of the excisional deviceand method according to the present invention.

FIG. 3B further shows the operation of an embodiment of the excisionaldevice and method according to the present invention.

FIG. 3C further depicts the operation of an embodiment of the excisionaldevice and method according to the present invention.

FIG. 4 shows a detailed view of a cutting tool suitable for use with theexcisional device according to the present invention.

FIG. 5 shows a cross section of the cutting tool, taken along line AA′in FIG. 4.

FIG. 6 shows a detailed view of another cutting tool suitable for usewith the excisional device according to the present invention.

FIG. 7 shows a cross section of the cutting tool, taken along line BB′in FIG. 6.

FIG. 8 shows another embodiment of a cutting tool suitable for use withthe excisional biopsy device according to the present invention.

FIG. 9 is a cross-sectional schematic of the tubular member 110, toillustrate the relative placements of the cutter window 120 and of thetransducer 270 about the circumference of the tubular member 110.Unnecessary details have been omitted for clarity.

FIGS. 10-17 show another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1A, 1B and 1C show an embodiment of the distal region 105 of theexcisional biopsy device 100 according to the present invention.Considering FIGS. 1A, 1B and 1C collectively, the distal region 105 ofthe excisional biopsy device 100 includes a generally tubular member 110having a generally tapered distal tip 115. The distal tip 115 isconfigured to penetrate soft tissue, such as breast tissue, lung tissue,liver tissue and the like. Preferably, therefore, the distal tip 115 andthe distal region 105 of the excisional biopsy device 100 present asmooth, and relatively atraumatic profile to the soft tissue in which itis designed to penetrate. Alternatively, the tip 115 may be sharplypointed and/or may include an energy source (not shown) to facilitatecutting through the tissue. The tubular member 110 may be formed ofrigid and hard plastic, or may be made of stainless steel, for example.Preferably, the tubular member 100 is used once and disposed of, forboth safety and functional reasons.

A cutter window 120 is disposed within the tubular member 110. Thecutter window 120 may be, for example, a shallow trench formed in thetubular member 110. As best seen in FIG. 1C, the cutter window 120 maybe a shallow and substantially rectangular trench in the tubular member110, or may be, for example, a thin, shallow I-shaped trench. Theexcisional biopsy device 125 includes a work element, such as a cuttingtool 125. The distal end of the cutting tool 125 is attached to thetubular member 110 near its distal tip 115. For example, the distal endof the cutting tool 125 may be attached to the distal-most point 121 ofthe cutter window 120. The cutting tool 125, however, may alternativelybe attached to other points within the distal region 105. The distalportion of the cutting tool 125 is exposed through the cutter window120. The remaining portion of the cutting tool 125 is disposed within aninternal guide or lumen 130 of the generally tubular member 110. Theinternal guide 130 constrains the movement of the cutting tool 125 andallows the cutting tool 125 to freely slide therein, parallel to thelongitudinal axis of the tubular member 110. With particular referencenow to FIG. 2C, the proximal portion 225 of the cutting tool 125 emergesfrom the internal lumen 130 near the proximal end 215 of the tubularmember 110. The proximal end of the cutting tool 125 may, for example,include a push or turn knob 226. The push or turn knob 226 allows theoperator of the excisional biopsy device 100 to selectively push thecutting tool 125 in the distal direction (away from the physician andtoward the distal tip 115) or retract the cutting tool 125 in theproximal direction (toward the physician and away from the distal tip115). To assist in controlling the movement of the cutting tool 125, thecutting tool is preferably biased in the proximal direction, assymbolized by the arrow 227 in FIG. 2C. This biasing may be effectuatedby means of a spring 228 attached at or near the proximal end 215 of thetubular member 110 and to the proximal portion 225 of the cutting tool125. In this manner, the default configuration of the cutting tool 125is the retracted position, wherein the cutting tool 125 liessubstantially flat within the cutter window 120 of the tubular member110.

The cutting tool 125, when pushed in the distal direction by thephysician applying pressure in the distal direction on the push or turnknob 226 or equivalent structure, slides within the internal guide 130of the tubular member 110. As the distal end of the cutting tool 125 isattached near the distal end of the tubular member 110 or to thedistal-most point 121 of the cutter window 120, the portion thereofexposed through the cutter window 120 tends to bow outwardly, extendingout of the cutter window 120, as shown in FIG. 1B. The extension out ofthe cutter window 120 and the degree of bowing may be controlled by thephysician, by appropriate action on the push or turn knob 226. Thus, thepossible range of extension and bowing is potentially infinite, beinglimited only by the physician's ability to control the cutting tool 125by finely pushing and retracting the push or turn knob 226. The degreeof extension, as well as the shape of the bowed portion of the cuttingtool, therefore, may be controlled by selectively sliding the cuttingtool within the internal guide 130 of the tubular member 110.

The shape of the bowed portion and the ease with which the distalportion of the cutting tool 125 bows outwardly may be varied by varyingthe physical characteristics of the cutting tool 125. Preferably, thecutting tool is formed of a resilient, readily deformable material that,when unstressed, returns to its original unbiased configuration. Forexample, a nickel titanium alloy may be used for the cutting tool 125,to allow the cutting tool 125 to exhibit shape-memory characteristics.The shape of the cutting tool 125 in its bowed and extendedconfiguration (FIG. 2) may be further controlled by varying, forexample, the thickness of the cutting tool over the portion thereofexposed through the cutter window 120. A locally thicker portion of thecutting tool 125 will not bend as readily as a locally relativelythinner portion thereof. Judiciously varying the thickness, for example,of the cutting tool 125, therefore, allows the curvature of the bowedportion thereof to be controlled.

As shown in FIGS. 1A, 1B, and with reference to FIG. 1C, pushing on thepush or turn knob 226 (or any such functionally equivalent structure)causes the cutting tool 125 to bow outwardly and extend out from thecutter window 120 of the tubular member 110, as shown in FIG. 1B.Similarly, retracting the push or turn knob 226 (or any suchfunctionally equivalent structure) causes the cutting tool 125 toflatten out within the cutter window 120 and to assume a configuration(shown in FIG. 1A) that may be substantially flush with the outersurface of the tubular member 110. In this configuration, the tubularmember 110 may easily penetrate soft tissue, such as breast, lung, liveror other soft body tissue.

In operation, the surgeon makes an incision into the patient's skin,such as the surface of the breast. The excisional biopsy device 100 thenmay be directly introduced into the breast tissue, or an expandablesheath (shown at reference numeral 495 in FIG. 13) may be introducedinto the incision and thereafter expanded as the excisional biopsydevice 100 is introduced therein. In any event, the excisional biopsydevice is introduced into the breast tissue itself and positioned, forexample, adjacent to the lesion in the breast or adjacent the targetsite from which the excision is to take place. During the introductionof the excisional biopsy device 100 into the soft tissue, the cuttingtool 125 is in its retracted configuration wherein the portion thereofexposed through the cutter window 120 is substantially flat. Theexcisional device 100, in this configuration, therefore, exhibits asmooth and tapered profile to the surrounding tissue. Once the device100 has been determined to have been properly positioned within the softtissue, the device is rotated about its longitudinal axis. The rotationmay be carried out manually, or the rotation of the device may becarried out by a motorized unit disposed within the proximal region ofthe device 100. As the device 100 rotates, the surgeon causes thecutting tool 125 to bow outwardly and to extend from the cutter window120. Preferably, the degree of bowing and outward extension is at leastsufficient to include the lesion (such as the targetedmicrocalcification within the breast) within the space between thecutter window 120 and the cutting tool 125. The cutting tool 125 cutsthe tissue as the device 100 is rotated, thereby severing the lesionfrom its surrounding breast tissue mass. By completing at least onerevolution within the breast tissue, the cutting tool 125 sweeps avolume of revolution of breast tissue and severs that volume from themain tissue mass. Such volume of revolution includes at least thetargeted lesion. Preferably, the volume of revolution severed from themain tissue mass not only includes the targeted lesion, but alsoincludes a margin of healthy tissue surrounding the lesion. The degreeof extension and bowing of the cutting tool 125 may be varied within agiven revolution of the excisional biopsy device 100. In this manner, itis possible to exert fine control over the amount of tissue cut awayfrom the main tissue mass, as well as fine control over the shape of thesevered mass.

After the lesion and preferably a margin of healthy tissue around thelesion have been severed, the severed tissue may be removed from themain tissue mass. This removal of the severed tissue may be effectuatedby any number of means, including the retraction of the excisionalbiopsy device 100 from the main tissue mass. Alternately, severed tissueextraction may be carried out by means of the structure and method to bedescribed below.

The cutting tool 125 may, as shown in FIG. 1C, be configured as a thinribbon. The thin ribbon 125 shown in FIG. 1C is preferably sharpened onits leading edge to facilitate cutting through tissue and sometimesfibrous and calcified masses. The leading edge of the cutting tool 125is that edge thereof that first comes into contact with the tissue to besevered as the device 100 is rotated. Such a sharpened leading edge isshown in FIG. 4 at reference numeral 127. The width of such a ribboncutting tool 125 is preferably smaller than the width of the cutterwindow 120 into which it recedes when the cutting tool 125 is retractedin the proximal direction.

Another embodiment of the cutting tool 125 is shown in FIG. 8. Todecrease the forward resistance of the cutting tool 125 as it slowlycuts through tissue, the leading edge of the portion thereof exposedthrough the cutter window 120 may be serrated, including a plurality ofteeth 127. In turn, the leading edge of the plurality of teeth 127 mayinclude a sharpened edge. In this manner, as the excisional device 100rotates, only the forward-most tips of the teeth 127 will initially comeinto contact with the tissue to be cut, thus reducing the tissue surfaceupon which the force of the rotating cutting blade 125 is applied. Thus,the cutting blade 125 of FIG. 8 is believed to be highly effective incutting through even relatively dense or fibrous tissue while minimizingthe torque to be applied to the excisional biopsy device 100 as it iscaused to rotate within the main soft tissue mass.

Referring to FIG. 4 and also to FIG. 5, the cutting tool 125 may furthercomprise an interior lumen 128 running an entire length or a portion ofthe length of the cutting tool 125. The cutting tool 125 may furtherinclude a plurality of through holes 126 in the distal portion of thecutting tool 125 exposed through the cutter window 120. The plurality ofthrough holes 126 are in fluid communication with the internal lumen128. In use, the internal lumen 128 may be connected, in the proximalportion of the excisional biopsy device 100, to a fluid reservoir. Thefluid reservoir, which may be internal or external to the proximalsection of the device 100, supplies the distal portion of the cuttingtool 125 with, for example, anaesthetic (such as, for example,lidocaine) and/or antibiotic fluid. In this manner, such anaestheticand/or antibiotic fluid (or other fluid) may be delivered precisely tothe tissue surrounding the cutting tool 125 as it rotates. A preciselydosed anaesthetic, for example, may be delivered to the very site whereit is most needed. As such anaesthetic is delivered only where it isneeded, the effect thereof is near instantaneous, and the patient feelslittle or no pain as the excisional biopsy device 100 according to thepresent invention is rotated within her breast, or other soft tissue.FIG. 5 shows a cross-section of the cutting tool 125 of FIG. 4, takenalong line AA′ in FIG. 4.

Care should be exercised in selecting the configuration and materialsfor the cutting tool 125 shown in FIGS. 4 and 5. Indeed, theconfiguration and materials selected should allow the cutting tool 125to bow and extend out of the cutter window 120 of the device 100without, however, pinching or substantially disrupting the flow of fluiddelivered via the internal lumen 128 of the cutting tool 125, if thecutting tool 125 is provided with such. For example, the cutting tool125 may be made of a shape-memory metal, such as nickeltitanium and/orthe proximal portion of the cutting tool 125 may be formed relativelythicker than other portions thereof.

Another embodiment of the cutting tool 125 is shown in FIGS. 15 and 16.As shown therein, the cutting tool 125 may be formed by a thin sheet ofsteel or shape memory alloy. The sheet may include a plurality ofthrough holes 126 to allow the anaesthetic or other fluid to beinstilled therethrough. A small tube 540 may be disposed on the sheet,aligned with the through holes 126. The sheet may be folded in thedirection indicated by the arrows 530, thus securing the tube 540between the two folded sides of the sheet. The edges 550 of the sheetmay be sealed together to render them fluid tight. For example, thesides 550 of the sheet may be welded together or secured by other meansknown to those of skill in the metal working arts. The edges 560 betweenthe through holes 126 may be sharpened, to allow the cutting tool 125 toefficiently cut through soft tissue. As shown in FIG. 16, the tube 540may deliver anaesthetic or other fluid to the cutting tool 125, whichdelivers minute amounts thereof precisely where it is needed: where thecutting edges 560 of the cutting tool 125, thereby affording the patientimmediate relief and minimizing the amount of anaesthetic that need bedelivered. The proximal end of the tube 540 may be in fluidcommunication with an anaesthetic reservoir (not shown) and/or ananaesthetic pump (also not shown).

Alternatively, the cutting tool 125 may include a thin wire, such asshown at 125 in FIGS. 6 and 7. In this case, an external radio frequency(hereafter, RF) power source 240 (shown at 240 in FIG. 2C) supplies thecutting tool 125 with RF energy via two bipolar electrodes (not shown)attached to the cutting tool 125 of FIG. 6. Other energy sources mayalso be used within the context of the present invention, RF power beingdiscussed herein for illustrative purposes only. The RF power deliveredby the RF power source 240 allows the cutting tool 125 of FIG. 6 tobecome an electrosurgical cutting and/or an electrocoagulating tool byselectively varying the power applied to the cutting tool 125. Suitablegenerators for such an electrosurgical cutting device 125 are known tothose of skill in this art. An example of such a suitable generator isdescribed in U.S. Pat. No. 4,903,696 issued Feb. 27, 1990 and assignedto Everest Medical Corporation, Brooklyn Center, Minn., the disclosureof which is incorporated herewith in its entirety. As with the cuttingtool 125 shown in FIGS. 4 and 5, the cutting tool 125 of FIGS. 6 and 7includes an internal lumen 128 and a plurality of through holes 126 toallow anaesthetic or other fluid to be delivered to the surroundingtissue as the cutting tool 125 cuts through the soft tissue as thedevice 100 is rotated.

As alluded to above, the excisional biopsy device 100 according to thepresent invention cuts out a (not necessarily symmetrical) volume ofrevolution as it cuts through the soft tissue upon rotation of thegenerally tubular member 110. This severed mass of tissue may bestabilized using an extendable tissue anchoring device, which anchoringdevice also assists in the retrieval of the severed tissue sample fromthe breast. The anchoring device may, for example, include a suctiondevice or other substantially rigid anchor member to anchor the tissuesample. Alternatively, the severed tissue sample may be collected in atissue collection device, as shown at reference numeral 260 in FIGS. 2Aand 2B. The tissue collection device 260 is attached externally to thetubular member 110, and preferably also to the trailing edge of thecutting tool 125. The tissue collection device 260 is preferably formedof a thin and flexible plastic membrane shaped like a bag. The openingof the bag-shaped collection device 260 is preferably co-extensive withthe opening 120 and is preferably attached to the tubular member 110 andto the trailing edge of the cutting tool 125. In this manner, theopening or “mouth” of the bag-shaped collection device 260 opens andcloses along with the bowing and retraction, respectively, of thecutting tool 125. Indeed, the “mouth” of the bag-shaped collectiondevice 260 is opened when the cutting tool 125 is bowed and extended outof the cutter window 120 and substantially closed when the same isretracted within the cutter window 120, as the two edges (one attachedto the tubular member 110 just adjacent to the edge of the cutter window120 and the other attached to the trailing edge of the cutting tool 125)of the collection device are then pressed together.

Therefore, when the excisional device 100 is inserted into soft tissueand rotated, the cutting tool 125 may be caused to bow and to extendoutwardly from the cutter window 120 and caused to cut tissue cominginto contact therewith. As the device 100 rotates and cuts, the tissuebetween the cutting tool 125 and the tubular member 110 tends to advancetoward and into the collection device. As the cutting tool 125 is in itsbowed and extended state, the “mouth” or opening of the bag-shapedcollection device 260 is also correspondingly open, allowing the severedtissue to collect therein. As the revolution of the tubular member 100is completed, the cutting tool 125 may be retracted and caused to assumea configuration wherein it is disposed within the recessed cutter window120, substantially flush with the outer surface of the tubular member110, as shown in FIG. 2B. In this configuration, the collection device260 is closed, thereby securing the excised tissue sample therein. Thedevice 100 may then be safely retracted from the main tissue mass, suchas the breast. As the excised sample is physically isolated from theremaining tissue mass, the probability of seeding the surrounding tissuewith potentially abnormal cells is markedly decreased. This probabilityis also further decreased, as the excisional device 100 according to thepresent invention allows the surgeon to obtain adequate margins ofhealthy tissue surrounding the target lesion by choosing the degree ofbowing and extension of the cutting tool 125. In this manner, theintegrity of the lesion itself is not violated, thereby maintainingtissue architecture intact.

As the collection device 260 is preferably formed of a thin and flexiblemembrane, it is able to lay substantially flat against the outer surfaceof the tubular member 110 or slightly recessed within the cutter window120 during insertion thereof into the soft tissue. The collection device260, therefore, offers little additional drag and resistance to thedevice 100 as it is inserted into the incision made in the patient'sskin during or prior to the procedure. Suitable materials for the tissuecollection device 260 include plastics and nylon, for example. Anystrong adhesive may be utilized to secure the tissue collection device260 to the tubular member 110 and to the cutting tool 125. Other meansof securing the collection device 260 may also be employed without,however, departing from the scope of the present invention. Likewise,the tissue collection device 260 may be formed of a material other thanspecifically enumerated herein while remaining within the spirit of thepresent invention. Preferably, the shape and size of the tissuecollection device 260 are such as to minimize drag on the excisionalbiopsy device 100 as it is inserted and rotated into the tissue. Forexample, the tissue collection device 260 preferably should be only aslarge as necessary to contain the excised tissue sample.

The excisional biopsy device 100 according to the present invention ispreferably accurately positioned adjacent to the lesion within thebreast or other organ. Toward that end, the present invention allows thesurgeon to gain near real time or real time information as to theinternal structure of the soft tissue during the procedure itself.Referring now back to FIGS. 1 and 2C, the present invention may includea transducer 270 mounted within the distal portion of the tubular member110. This transducer 270 is preferably adapted to image tissue about tobe cut by the cutting tool 125 as the excisional biopsy device 100 isrotated within the soft tissue. Indeed, the transducer 270 preferablygenerates information relative to the tissue about to be cut—that is,tissue that that has not yet been brought into contact with the cuttingtool 125 as the tubular member 110 rotates about its longitudinal axis.In this manner, as the rotational speed of the excisional biopsy device100 is preferably quite slow (the rotation may be manually carried outor may be caused by a slow moving motorized unit attached to the tubularmember 110), the surgeon may evaluate the information generated by thetransducer 270 and may, based upon this information, vary the degree ofbowing and extension of the cutting tool 125. For example, when thedevice 100 is positioned adjacent to the lesion of interest and rotated,the transducer 270 will detect the presence and location of the lesionbefore the lesion comes into contact with the cutting tool 125. Afterthe lesion has been detected by the transducer 270, the surgeon may pushon the push or turn knob 226 or other structure that causes the cuttingtool to bow and extend from the cutter window 120. The lesion (andpreferably an adequate margin of healthy tissue) will then be severedfrom the main mass, and optionally collected, for example, in the tissuecollection device 260. When the transducer 270 indicates that therotation of the tubular member has brought the cutting tool 125 past thelesion, the cutting tool 125 may be retracted within the cutter window120. The cutting, it can be seen, may be specifically tailored to thesize and shape of the lesion within the main tissue mass in near realtime or in real time, thereby allowing the surgeon to excise all of thetissue required and only the tissue that is necessary to achieve theintended results.

Preferably, the transducer 270 is an ultrasound sensor mountedsubstantially flush with the external surface of the tubular member 110.The ultrasound sensor 270 is preferably electrically connected, via acommunication channel such as electrical conductors, to at least onedata processing and display device, shown at reference 250 in FIG. 2C.The data processing and display device(s) 250 allows the surgeon to see,in near real time or in real time, the internal structure of the tissueabout to be cut by the cutting tool 125. This allows the surgeon notonly to see a graphical representation of the internal structure of thetissue during the procedure itself, but also allows the surgeon toassure himself or herself that the entire lesion or group of lesions hasbeen properly excised by, for example, rotating the tubular devicewithin the tissue while the cutting tool is retracted within the cutterwindow 120 while the transducer 270 is energized. Viewed from anotheraspect, therefore, the present invention is an intra-tissue ultrasoundimaging device that may, but need not include a cutting tool, such asreferenced by numeral 125 in the figures.

In operation, the (e.g., ultrasound) transducer sweeps a plane(graphically shown at 280 in FIG. 3A) within the tissue ahead of thework element, such as cutting tool 125. In selecting the operationalcharacteristics of the ultrasound transducer 270, the surgeon mustbalance the required resolution (i.e., the smallest feature that must bediscernable) with the degree of penetration of the ultrasound waveswithin the tissue and the intensity of the ultrasonic waves generated.In general, higher frequencies allow better resolution. However, highfrequencies do not penetrate the tissue as far as do lower frequencyultrasound waves. Preferably, the ultrasound transducer 270 is tunedwithin the range from about 5 MHz to about 20 MHz. More preferably, theultrasound transducer 270 is tuned within the range of about 7.5 MHz toabout 20 MHz. For example, in the case wherein the excisional biopsydevice 100 according to the present invention is used within the femalebreast, the ultrasound transducer may be tuned within the range of about10 MHz to about 13 MHz.

To effectively image the internal tissue structure prior to cutting itwith, for example, the cutting tool 125, the transducer 270 must bepositioned within the tubular member 110 away from the cutting tool 125.With reference to FIG. 9, the transducer 270 may be disposed within thetubular member at an angle α relative to the cutting tool 125. The angleα is preferably no smaller than that necessary to effectively controlthe operation of the work element (such as cutting element 125) inresponse to information gathered from the transducer 125 as the tubularmember 110 rotates. This angle α, therefore, is dependent at least uponthe rotational speed imposed upon the tubular member 110 and upon thetime necessary for the surgeon to assimilate the information generatedby the transducer and to effectively control the cutting tool 125 inresponse to such information. Preferably, the angle α is less than about180 degrees.

When used in conjunction with an intra-tissue ultrasound transducer,such as shown at 270, the excisional biopsy device 100 according to thepresent invention may include a variety of work elements in place of orin addition to the cutting tool 125. Such work elements include, forexample, an abrasive device, a reciprocating cutting device, anelectrosurgical device or a vibrating device.

In the case of lesions within the breast, it is useful to stabilize thebreast prior to imaging and performing invasive procedures. Suchstabilization is conventionally performed by compression plates thatsqueeze the breast and compress the tissue therein. Such compression isnecessary to allow x-ray radiation, as used in mammography, to produce auseful image. Although such compression is not needed or believed to bedesirable according to the present invention, stabilization of thebreast remains necessary. For this purpose, the breast stabilizationdevice described in commonly assigned U.S. patent application Ser. No.09/158,215, filed Sep. 22, 1998, the disclosure of which is incorporatedherein in its entirety, may be useful.

Reference is now made to FIGS. 3A, 3B and 3C, which illustrate anembodiment of the excisional biopsy method according to the presentinvention. Although FIGS. 3A-3C illustrate an embodiment of the presentinvention within the context of breast surgery, it is to be understoodthat the present inventive method is equally applicable to other softtissue masses, such as, for example, lung, thyroid or liver tissue, withonly minor modifications which will become apparent to skilledpractitioners in this art.

Turning first to FIG. 3A, a small incision 331 is made in the breast310, preferably in the peri-areolar region. Preferably, the breast isstabilized, using, for example, the breast stabilizing device disclosedin U.S. patent application Ser. No. 09/158,215 referred to above. Theportion of the device 100 that remains outside of the soft tissue mayinclude attachment means (not shown) for clamping the device to a rimstructure, for example, to allow stable operation and precise guidancethereof. The small incision is preferably made on the border of theareola 330 surrounding the nipple 320, as this provides a bettercosmetic scar than on the skin on the side of the breast 310. Dependingon the size of the lesion and the size of the excisional biopsy device100 to be inserted therein, an expandable sheath (an example of which isshown at reference numeral 495 in FIG. 13) may be inserted into thebreast tissue. In any event, the excisional biopsy device 100 isinserted into the breast tissue and positioned adjacent the lesion 300,which may be, for example, a microcalcification or other abnormallesion. Once in position, the device 100 is rotated, for example, in thedirection indicated in FIG. 3A. The portion of the excisional biopsydevice 100 that remains outside the soft tissue may have a greaterdiameter than the portion thereof that is designed to penetrate the softtissue. This aids in manual rotation of the device 100. In theconfiguration depicted in FIG. 3A, the cutting tool 125 is retractedwithin the cutter window 120 and the tissue collection device 260, ifpresent, is substantially flat against the external surface of thetubular member 110. The device 110 is rotated about its longitudinalaxis and the transducer 270 is energized, the, information therefrombeing transmitted to, for example, the display device 250 shown in FIG.2C. When the lesion 300 comes into view, the surgeon then gauges thesize, shape and location thereof and controls the bowing and extensionof the work element, such as cutting tool 125 based on the informationreceived from the transducer 270 and displayed upon the display 250.FIG. 3B depicts the situation wherein the lesion 300 has been imaged andthe surgeon has extended the cutting tool 125 to sever the lesion 300from the surrounding breast tissue. The severed tissue may be receivedand collected in a tissue collection device 260, as the device 100rotates. Anaesthetic and/or antibiotic (or other) fluids may bedelivered directly to the affected tissue by through holes 126 (bestseen in FIGS. 2A, 2B and FIGS. 4-7), greatly decreasing pain during theprocedure

After the lesion and any desired margin of healthy tissue is severedfrom the main breast tissue mass, the cutting tool 125 is retractedwithin the cutter window 120. This closes the tissue collection device260, if present, and allows the entire device 100 to be retracted fromthe breast in the direction of arrow 350, as shown in FIG. 3C. If thetissue collection device 260 is present, the lesion 300 will be isolatedfrom surrounding tissue by the membrane of the tissue collection device260, thus minimizing any possibility of seeding potentially abnormalcells to surrounding breast tissue. Moreover, the tissue architecture ofthe retrieved lesion 300 is substantially preserved, thereby allowingaccurate histopathology to be performed upon the entire mass excisedfrom the breast. Indeed, any compression such tissue may undergo isbelieved to be solely due to the retraction of the device back throughthe entrance track of the device 100 in the uncompressed breast tissue.Thereafter, when the excisional device 100 is removed from the breast310, the push or turn knob 226 may be acted upon to extend and bow thecutting tool 125, thereby allowing the excised lesion to be retrievedfrom the tissue collection device 260 for examination. If the tissuecollection device is not present, conventional suction means may beemployed to extract the severed lesion from the surrounding breasttissue. Bleeding is controlled by suitably varying the RF or other powersource applied to the electrosurgical cutting tool 125, if present, tostem the bleeding by cauterizing the tissue coagulating the blood.

After the procedure, a small cavity remains in the breast where thelesion had previously been. However, since no compression of the breastwas carried out, no expansion of the tissue occurs after the procedure,unlike conventional techniques. Therefore, the cavity and the entranceand exit path of the device remain as small as possible, leading tofewer complications, less tissue trauma and improved aesthetics.

According to another embodiment of the present invention, shown in FIGS.10, 11 and 12, the transducer 270 is replaced by a removable transducercore 400. The removable transducer core 400 includes an active element440 configured to perform intra-tissue imaging and of relayinginformation back to a display device (shown in FIG. 14) via acommunication channel, such as shown at reference numeral 460. Thecommunication channel 460 may be wireless or may include, for example,optical fibers and/or electrical conductors. The active element 440 maydraw power from an internal battery (not shown) or from a power source,such as shown at reference numeral 480. The active element 440 mayinclude an ultrasound transducer. Other types of transducers may be usedinstead of or in addition to an ultrasound transducer. The removabletransducer core 400 preferably includes a generally tubular shaft 430. Aproximal section 450 is included near the proximal portion of thetransducer core 400.

To accommodate the removable transducer core 400, the excisional device100 of FIG. 10 includes an internal lumen 420 through which theremovable transducer core 400 may be inserted. Preferably, theexcisional device 100 is used once and disposed of, for safety andfunctional reasons. The removable transducer core 400, however, mayeither be disposable or re-usable for a limited number of uses. To allowthe active element 440 of the transducer core 400 to image the lesion tobe excised and the surrounding tissue, the generally tubular member 110of the excisional device 100 includes a transducer window 410. When theremovable transducer core 400 is inserted within the internal lumen 420,the proximal section 450 of the core 400 preferably snaps into a lockedconfiguration with the proximal end of the excisional device 100. Whenin its locked configuration, the active element 440 of the transducercore 400 is aligned with and faces the transducer window 410, to allowthe active element 440 to image the lesion and the surrounding tissuetherethrough.

FIG. 11 shows an embodiment of the removable core 400 according to thepresent invention. As the removable core 400 may advantageously be usedindependently of the excisional device 100, the removable core 400includes a distal tapered tip 470, to allow it to easily penetrate softtissue. Moreover, its thin profile allows the surgeon to insert theremovable core 400 within soft tissue without, however, unduly damagingthe tissue or making a large incision. The removable core 400 allows thesurgeon to precisely localize the lesion to be excised from within thetissue itself. For example, the active element 440 of the removable core400 may include an ultrasound transducer having similar characteristicsas the sensor 270, and may be used alone or in addition to surfaceultrasound to localize the lesion with a great degree of precision.

FIG. 12 shows a cross section of the embodiment of the excisional device100 of FIG. 10, taken along line AA′. As shown in FIG. 12, the cuttingtool 125 is exposed through the transducer window 120. The window 120may, as shown in FIG. 12, include support guides 122 to support andguide the cutting tool 125 as it is outwardly extended and bowed. Thetissue collection device 260, for clarity, is not shown in either FIGS.10 or 12. However, to accommodate the bulk of the excised tissue samplecollected in the tissue collection device 260 after the cutting andcollecting operation described herein, the tubular member 110 mayinclude a recessed section 131. The recessed section provides space forthe collected (e.g., bagged) tissue sample in the tissue collectiondevice 260 when the excisional device is removed from the soft tissuemass. In this manner, the collected tissue sample within the tissuecollection device 260 does not protrude from the generally smooth outersurface of the excisional device 100 upon retraction of the latter fromthe soft tissue mass from which the tissue sample is excised. Theinternal lumen 420 allows the removable core 400 to slide therein and toproperly position the active element 440 facing the transducer window410.

FIG. 13 shows the removable core 400 inserted within an expandablesheath 495. The expandable sheath includes a proximal base section 510.Attached to the proximal base section 510 is a generally cylindricalexpandable meshwork 500 of, for example, plastic or nylon fibers. Themeshwork 500 may be somewhat tapered at its distal end 520, to provide asmooth transition between the expandable meshwork 500 and the removablecore device 400. The proximal section 450 of the core 400 may snap-fitto the proximal base section 510 of the expandable sheath 495, so as tobe securely and removably attached thereto. As shown in FIG. 13, theexpandable meshwork 500 expands just enough to accommodate the removablecore 400 inserted therein. In practice, the expandable sheath 495 andremovable core 400 assembly may be inserted within the soft tissuetogether, to allow the surgeon to image the lesion prior to insertingthe somewhat greater diameter excisional device 100 therein. Thereafter,the surgeon may retract the removable core 400 from the expandablesheath 495, leaving the expandable sheath 495 in place within the softtissue, such as the breast.

FIG. 14 shows another embodiment of a soft tissue excisional deviceassembly 600 according to the present invention. In the configurationshown in FIG. 14, the removable core 400 is inserted and secured withinthe excisional device 100 so that the active element 440 faces out ofthe transducer window 410. As in FIG. 10, the tissue collection device260 is not shown, for clarity. In FIG. 14, the excisional device 100 isshown inserted within the expandable sheath 495. Indeed, the excisionaldevice 100, in FIG. 14, is shown inserted within and past the distal end520 of the meshwork 500, so the distal portion of the excisional device100 including the cutting tool 125 and the transducer window 410 extendstherethrough. The meshwork 500, in FIG. 14, has expanded to accommodatethe diameter of the excisional device 100. The proximal portion of theexcisional device 100 may extend from the proximal base section of theexpandable sheath 495. This allows the push or turn knob 226 (a turnknob 226 shown in FIG. 14) to be manually accessible to the surgeon. Anumber of peripheral devices may be connected to the assembly 600.Examples of such include a core power source 480, which may be, forexample, an electrical source for an ultrasound transducer, one or moredata processing and display devices 250 on which the internal structureof the tissue imaged by the active element 440 of the core 400 may bedisplayed, suction means 490, a cutting tool power source (a variable RFenergy source, for example), and/or other devices 590. The suctiondevice 490 may provide a suction force to the window 120 through aninternal lumen to facilitate cutting of the tissue by the cutting tool125.

The excisional device assembly 600 may be rotated in toto, or theexcisional device 100 may be rotated independently of the expandablesheath 495, depending upon the degree of friction between the two.Preferably, the excisional device 100 is removable from the expandedsheath 495 shown in FIG. 14, while leaving the expanded sheath 495 inplace within the soft tissue. In this manner, after retraction of theexcisional device 100 from the sheath 495, the sheath 495 remains inplace within the soft tissue to allow other instruments to be insertedtherethrough. For example, the removable core 400 may, after theexcisional procedure proper, be re-inserted through the expanded sheath495 to the excision site. Thereafter, the surgeon may cause the activeelement 440 of the removable core 400 to become energized, to image theexcision site to insure that the complete lesion has been removed fromthe soft tissue mass. To do this, the surgeon may rotate the removablecore 400 within the expanded sheath 495 while observing the display ordisplays for signs of the lesion. If none is found, it is probable thatthe entire lesion has been successfully removed and the surgeon may thenretract the core 400 from the sheath 495 and the sheath from the tissuemass and repair the incision made prior to inserting the assemblytherein. Alternatively, the surgeon may choose to remove both theexpanded sheath 495 and the core 400 simultaneously.

FIG. 17 shows an embodiment of the method of excisional biopsy methodaccording to the present invention. In FIG. 17, it is assumed that thesoft tissue from which the lesion is to be excised is breast tissue andthat the active element 440 of the removable core 400 is an ultrasoundtransducer. Other combinations are possible, and the present inventionshould not be limited to applications related to breast tissue andultrasound. The removable core 400 and the active element 440, in FIG.17, are together abbreviated as “US CORE”, a shorthand expression forthe phrase “ultrasound core” and the word “assembly” is abbreviated to“Ass'y”. Moreover, it is to be understood that the steps shown in FIG.17 constitute but a broad outline of one possible embodiment of thepresent inventive method. Therefore, other additional steps may beinserted between the steps shown in FIG. 17, or other steps may besubstituted for some of the displayed steps without, however, departingfrom the scope of the present invention.

The method starts at step S0. In step S1, the lesion within the breastis grossly targeted, using, for example, standard or stereotacticsurface ultrasound. In step S1, a rough estimate of the location of thelesion within the breast is obtained. The surgeon, after having locatedthe general location of the lesion, may mark the location thereof on theultrasound display or displays and/or on the corresponding surface ofthe breast, with an “X”, for example. The breast is stabilized in stepS2. Preferably, the breast is stabilized in an uncompressed or slightlyexpanded state, in the manner disclosed in the commonly assigned andco-pending U.S. patent application Ser. No. 09/158,215 previouslydiscussed and incorporated by reference herein. The woman's other breastis preferably placed within a counterpart breast stabilizing device,which helps to immobilize the woman during the procedure. One of theultrasound ports of the breast stabilizing device is aligned with thelesion, for example, by aligning one of its ultrasound ports with themarked location on the breast. Suction is then applied to the breaststabilizing device, in the manner described in the above-referencedapplication and a correctly oriented surface ultrasound device issecured to the ultrasound port of the stabilizing device. Other means ofstabilizing the breast may also be used without, however, departing formthe present invention.

In step S3, an entry site on the breast is chosen. Preferably, theperi-areolar region is chosen as the incision site, as scars within theperi-areolar region are less visible than scars in more exposed regionsof the breast and for other anatomical reasons. The incision site isthen anaesthetized, both on the skin surface and subcutaneously. Also instep S3, a small incision is made at the chosen incision site.Preferably, the incision is large enough to accommodate the expandablesheath 495 with the removable core 400 inserted therein. In step S4, theexpandable sheath 495, together with the removable core insertedtherethrough, is inserted into the incision made in step S3. Undersurface ultrasound guidance, for example, the sheath 495/core 400assembly is navigated adjacent to the lesion. If the sheath 495/core 400assembly can be properly positioned adjacent to the target lesion, themethod according to the present invention proceeds to step S5. If thesheath 495/core 400 assembly cannot be properly positioned adjacent tothe target lesion, all or a portion of the above-detailed steps arerepeated until proper positioning of the sheath 495/core 400 assembly isachieved, adjacent to the target lesion.

Assuming now that step S4 has been completed to the surgeon'ssatisfaction, the core 400 is removed from the expandable sheath 495 andthe expandable sheath 495 is left in place within the breast, as shownin step S5. In step S6, the removable core 400 is inserted within theinternal lumen 420 of the tubular member of the excisional device 100and locked securely in place, so that the active element 440 (in thiscase, an ultrasound transducer) is aligned with and faces out of thetransducer window 410 of the device 100. Again leaving the expandablesheath 495 in place within the breast, the excisional device 100 (withthe core 400 secured therein) is advanced through the expandable sheath495. The sheath 495 then expands within the breast tissue to accommodatethe somewhat larger diameter of the excisional device 100. Theexcisional device 100 is advanced past the tapered distal end 520 of thesheath 495, so the assembly including the sheath 495, the excisionaldevice 100 and the removable core 400 is positioned adjacent to thetarget lesion within the breast tissue, as shown in step S7.

In step S8, the correct position adjacent the target lesion and thecorrect rotational orientation of the aforementioned assembly (FIG. 14)is confirmed, using surface ultrasound and/or the core ultrasound 400.The active element 440 of the core 400 is particularly well suited forthis task, as the excisional device 100 may be rotated within thetissue, and positioned so the cutting tool 125 is properly positioned toallow it to rotate, extend and bow outwardly in such a manner as toprecisely sever the lesion from the surrounding tissue with an adequatemargin of healthy tissue. Indeed, the ultrasound transducer 440, as itrotates along with the excisional device 100, images the lesion beforethe cutting tool 125 cuts it, thereby allowing the surgeon to optimallydeploy the cutting tool based upon his or her observation of the imagedtissue on a display or displays. In step 9, the surgeon may activate ananaesthetic infusion, the anaesthetic being delivered by the cuttingtool 125 via the plurality of through holes 126, best seen in FIGS. 4and 6. Step S9 may be skipped if the cutting tool 125 does not providefor through holes 126 or if the surgeon does not deem it necessary toanaesthetize the tissue during the rotation of the cutting tool 125. Forexample, the tissue may have been previously anaesthetized. Whilerotating at least the excisional device 100 (with the removable core 400secured therein), the cutting tool 125 is extended using, for examplethe push or turn knob 226 shown in FIGS. 2C and 14, thereby causing thecutting tool 125 to extend from the window 410 and to bow outwardly, asshown in step S10. Depending on the amount of friction between theexcisional device 100 and the expandable sheath 495 (which may be freelychosen depending upon the choice of material for the meshwork 500 andthe configuration of the mesh), the sheath 495 may rotated along withthe excisional device 100. The degree of extension and bowing may befinely controlled by the surgeon as the excisional device 100 isrotated, either manually or by a motorized unit (not shown) coupledthereto. As the cutting tool is rotated, the severed tissue sample ispreferably collected (e.g., bagged) in a tissue collection device 260(FIGS. 2A and 2B), as shown at step S11. The blood vessels may becoagulated as the cutting tools rotates and cuts the tissue, orafterwards. In step S12, after the excisional device 100 has completedat least one revolution within the breast and has cut a volume ofrevolution therein, including at least the target lesion and preferablya margin of healthy tissue surrounding the lesion, the excisional biopsydevice 100 and removable core 400 assembly are retracted through thesheath 495, leaving the sheath 495 once again in place within thebreast. Preferably, the tissue collection device 260 and the tissuesample it encloses lie within the recessed section 131 of the generallytubular member 110. In this manner, the filled collection device 260does not protrude or protrude too much from the surface of the tubularmember 110, thereby allowing the retrieved tissue sample to be readilyretracted with the excisional device 100 through the sheath 495.

After retraction of the excisional device 100, the core 400 may beretracted from the device 100 and re-inserted through the sheath 495left in place within the breast. The core 400 is then advanced adjacentto the excision site, and rotated to allow the surgeon to image theexcision site to insure that the entire lesion has indeed been removed,as shown in step S13. Some or all of the above steps may be repeatedshould the imaging of the excision site by the core 400 within thesheath 495 reveal that a portion of the target lesion was not excised.Assuming that all of the target lesion has been removed, the incision isrepaired by, for example, suturing the peri-areolar incision site. Themethod ends at step S16.

While the foregoing detailed description has described severalembodiments of this invention, it is to be understood that the abovedescription is illustrative only and not limiting of the disclosedinvention. For example, the shape of the cutting tool 125 may differfrom that shown in the Figures. Other transducers and/or work elementsmay be added or substituted for those shown and described herein. Forexample, a piezoelectric transducer may be advantageously utilized tovibrate the cutting tool 125 at high frequencies. A number of othermodifications will no doubt occur to persons of skill in this art. Allsuch modifications, however, should be deemed to fall within the scopeof the present invention. Thus, the invention is to be limited only bythe claims as set forth below.

What is claimed is:
 1. An invasive interventional device for softbiological tissue, comprising: a rotatable tubular member having adistal tip adapted to penetrate the tissue; a work element disposed nearthe distal tip of the tubular member, the work element acting upon thetissue coming into contact therewith as the tubular member rotates; anultrasound transducer disposed near the distal tip of the tubular memberand away from the work element, so that the transducer sweeps a planewithin the tissue ahead of the work element as the tubular memberrotates; and means for controlling an operation of the work elementbased upon information gathered from the ultrasound transducer.
 2. Thedevice of claim 1, wherein the ultrasound transducer is tuned within arange from about 7.5 MHz to about 20 MHz.
 3. The device of claim 1,wherein the ultrasound transducer is disposed within the tubular memberat an angle α relative to the work element, the angle α being no smallerthan that necessary to effectively control the operation of the workelement in response to the information gathered from the transducer asthe tubular member rotates.
 4. The device of claim 3, wherein the angleα is less than about 180 degrees.
 5. The device of claim 1, wherein thework element comprises at least one device selected from the groupconsisting of: an abrasive device, a reciprocating cutting device, abowing cutting device, an electrosurgical device, a laser device and avibrating device.
 6. The device of claim 1, wherein the ultrasonictransducer is connected to at least one data processing and displaydevice to allow an operator of the device to ascertain a structure ofthe tissue and to control the operation of the work element before thetissue comes into contact with the work element as the device rotates.7. The device of claim 1, wherein the work element comprises a cuttingtool, a distal end of the cutting tool being attached near the distaltip of the tubular member, at least a distal portion of the cutting toolbeing configured to selectively bow out of a window in the tubularmember and to retract within the window.
 8. The device of claim 7,wherein the controlling means include means for selectively bowing andretracting the cutting tool.
 9. The device of claim 8, wherein thecontrolling means includes one of a manually operable push knob and amanually operable turn knob.
 10. An excisional device for soft tissue,comprising: a rotatable tubular member including a distal tip adapted topenetrate the tissue; an RF work element disposed near the distal tip ofthe tubular member; and an imaging device disposed near the distal tipof the tubular member and away from the RF work element, the imagingdevice being configured to image the tissue ahead of the work element asthe tubular member is rotated.
 11. The excisional device of claim 10,wherein the RF work element is coupled to an external variable RF energysource.
 12. The excisional device of claim 11, wherein the variable RFenergy source is configured to enable an RF power applied to the RF workelement to be varied to enable selective cutting and coagulating of thetissue.
 13. The excisional device of claim 11, wherein the RF workelement includes two bipolar electrodes coupled to the external variableRF energy source.
 14. The excisional device of claim 10, wherein theimaging device is configured to be removable from the tubular memberwhile the tubular member remains in the tissue.
 15. The excisionaldevice of claim 10, wherein the imaging device includes an ultrasoundtransducer tuned within a range from about 5 MHz to about 20 MHz. 16.The excisional device of claim 11, wherein the imaging device isdisposed within the tubular member at an angle α relative to the workelement, the angle α being no smaller than that necessary to effectivelycontrol the operation of the work element in response to the informationgathered from the imaging device as the tubular member rotates.
 17. Theexcisional device of claim 16, wherein the angle α is less than 60degrees.
 18. The excisional device of claim 10, wherein the imagingdevice is connected to at least one data processing and display deviceto allow an operator of the excisional device to ascertain structuralcharacteristics of the tissue and to control the operation of the RFwork element before the tissue comes into contact with the RF workelement as the device rotates.
 19. The excisional device of claim 10,wherein the RF work element comprises a cutting tool, a distal end ofthe cutting tool being attached near the distal tip of the tubularmember, at least a distal portion of the cutting tool being configuredto selectively bow out of a window in the tubular member and to retractwithin the window.